The stairwell is the bright core of the house. To keep an open feeling, and costs down, it zigzags its way up. Inexpensive metal railings are set inside and painted the same red to disappear into the stairwell.
When residents want privacy (from the outside world or from other family members), sliding curtains, like this one dividing the office from the staircase, create temporary walls between rooms. "When you close the curtains, you can't see anything," says Wibowo. "It's more like Asian culture, where you don't want to show everything all at once. We want to be in control of what guests see."
To mirror the mountaintop, Wibowo drew three points at the top of the roof (one at the apex, two at intermediate points), then connected all the walls off at least one of those points. The result is a jagged yet sliding set of angles capping the structure. Inside, the top of the house is like a bright white snowcap.